On the Conformal Symmetry of Exceptional Scalar Theories

Understand

The DBI and special galileon theories exhibit a conformal symmetry at unphysical values of the spacetime dimension.

• We find the Lagrangian form of this symmetry.
• The special conformal transformations are non-linearly realized on the fields, even though conformal symmetry is unbroken.
• Commuting the conformal transformations with the extended shift symmetries, we find new symmetries, which when taken together with the conformal and shift symmetries close into a larger algebra.